TM 5-4210-224-14 & P
4-226. POWER STEERING SYSTEM MAINTENANCE (Continued).
(10) Have the steering wheel turned into the
If the flow drops more than 1 gpm
left and then right. Corner lightly against
the wheel stops. Record the pressure and
disassemble the pump and replace
the ring, rotor, and vanes. If the
pressure plates are worn or
Pressures developed in both
cracked, replace them. Replace
corners should be nearly the same
all o-ring seals when reassembling
as the maximum pump output. At
the pump. Continue the test.
the same time, the flow should
drop below 0.5 gpm (1.85 L/min.).
(7) Completely close and partially open the
gate valve three times (do not allow the
If the pressure does not reach
valve to remain closed for more than 5
maximum output or the flow does
Record the "gate closed"
not drop below the specified value,
excessive internal leakage is
(8) If the pump pressure recorded is 100 psi
disassemble the steering gear and
(690 kPa lower than 1350 psi (9308 kPa)
remove control valve or replace
replace the flow control valve in the
the steering gear.
pump. If the pressure recorded is above
1450 psi (9998 kPa) the flow control valve
(11) Have the steering wheel turned slightly in
in the pump should be removed and
both directions and released quickly while
cleaned or replaced. If the system is
watching the pressure gauge. The needle
exceptionally dirty, both the steering gear
should move from the normal back
pressure reading and snap back as the
wheel is released. If it comes back slowly
reassembly, or replaced.
or sticks, the rotary valve in the steering
(9) Increase the engine speed from idle to
gear is sticking. Remove, disassemble,
about 1500 rpm. Record the flow.
and clean the rotary valve. If the system
contains a lot of dirt and foreign material,
disassemble the pump, the gear, clean
If flow varies more than 1 gpm
and reassemble, or replace.
from flow, then the flow control
(12) If the problem still exists, the steering and
valve should be removed and
front suspension must be thoroughly
cleaned or replaced, the same as
in step (8).